This invention relates to apparatus for visually aligning reference points on a damaged vehicle and for visually determining the extent of deviation of such reference points from set or known standards.
Various apparatus or equipment are known for correcting misalignment of vehicles by returning frame and body members of vehicles back to their predamaged locations. Equipment of this nature is utilized by personnel in body shops and other service and repair shops. Typical of such equipment is the apparatus disclosed in U.S. Pat. No. 3,630,066 entitled "Apparatus for Returning Vehicle Body and Frame Components to Their Original Locations During Repair and Servicing of Vehicles," issued Dec. 28, 1971, and U.S. Pat No. Re. 31,636 entitled "Auto Body and Frame Straightening Device", reissued July 1, 1984 on a patent issued June 10, 1975. Both of the referenced patents are incorporated herewith by reference.
The effective use of such equipment in the process of applying pulling forces to a vehicle body is enhanced by various gauging and measuring systems that provide an indication of the magnitude of misalignment or deviation of the component parts of the vehicle body to an operator of the alignment equipment. There are many such measuring systems that have been disclosed in prior art patents including the following:
______________________________________ Pat. No. Inventor Title Issue Date ______________________________________ 3,869,804 Friend Vehicle Frame Alignment 3/11/75 Gage 4,165,567 Olsson Checking and Measurement 8/28/79 Device for Automotive Chassis 4,207,681 Bayorgeon, Vehicle Measuring Bridge 6/17/80 et al. 4,302,883 MacGregor Vehicle Frame, Body and 12/1/81 Wheel Alignment Gauge 4,342,154 Legrand Measuring Bridge 8/3/82 4,366,624 Bergstrom Arrangement for Benches 1/4/83 for Measuring and Straightening Vehicles 4,479,305 Wendl, Measuring Bridge 10/30/84 et al. 4,490,918 Clausen Vehicle Frame Measure- 1/1/85 ment Device 4,513,508 Jarman, Vehicle Body and Frame 4/30/85 et al. Measuring Device 4,523,384 Giacomini Method and Apparatus for 6/18/85 Measuring Deviations in Vehicle Bodies or Frames ______________________________________
Typically, these prior art patents disclose a framework which is attached to a vehicle body or to a platform which supports a vehicle body. The framework includes various scales and associated slidable or fixed pointers. The pointers may be aligned with selected reference points of the vehicle body. The distance between a selected reference point and a fixed, known reference point (known as a datum point) is then measured. If the measured distance varies from known specifications, then the selected reference point is not in the required or standard position. Frame straightening equipment may then be utilized to bend and reform the vehicle body and thereby move the selected reference point to its required or standard position.
One of these very basic measuring or gauging systems comprises a series of transverse bars which are suspended at spaced intervals along the longitudinal axis beneath an automobile. Typically the bars are attached at their opposite ends to the underframe of the vehicle so that a center line pointer supported by each bar is located at the center line of the vehicle. If the vehicle frame or body is undamaged, the center line pointer of each transverse bar will lie on a common longitudinal axis of the vehicle and the transverse bars will lie in a common horizontal plane. On the other hand, if the vehicle frame or body is damaged, there will be misalignment of the pointers and bars.
By applying appropriate strains to the frame and body using frame straightening equipment, the damaged frame or body can be reformed to its orginal specification condition. Such reformation is visually ascertainable by observation of the center pointers and transverse bars. Once such pointers and bars are aligned, the frame has been straightened.
The general construction and theory of operation of the pointers and transverse bars used in such a system are well known to those of ordinary skill in the art. Typical of such constructions are those depicted in the following patents:
______________________________________ Pat. No. Inventor Title Issue Date ______________________________________ 1,404,096 Decatur Centering Device 1/17/22 2,000,866 Smith Chassis Checking Gauge 5/7/35 2,401,980 Smith Means for Gauging 6/11/46 Vehicle Frames 2,481,420 Hanson Hydraulic Action Center 9/6/49 Gauge 2,575,194 Smith Motor Vehicle Frame 11/13/51 Alignment Measuring Mechanism 2,581,021 Jacobsen, Bilaterally and Uniformly 1/1/52 et al. Extensible Unit 3,057,074 Sidwell Automobile and Truck 10/9/62 Frame Body Alignment Gauges 3,151,396 Junkins Vehicle Frame Gauge 10/6/64 3,611,575 Chartier Auto Frame Alignment 10/12/71 Apparatus 3,786,572 Larson Gauge for Use in 1/22/74 Straightening Automo- tive Frames 3,810,313 Hicks Vehicle Frame Gauge 5/14/74 3,983,635 Jarman Auto Frame Gauge 10/5/76 4,006,532 Hallman Gauge for Measuring 2/8/77 Vehicle Frame Alignment 4,015,339 Horvallius Measuring Tool for 4/5/77 Frameworks 4,375,131 Jarman, Vehicle Frame Datum Line 3/1/83 et al. Reference System 4,441,259 Leitermann, Method and Means for In 4/10/84 et al. Situ Determination of Alignment of a Vehicle Frame ______________________________________
Systems of this type are very useful. However, their utility is dependent upon the ease of adjustment of the transverse bars among other things. Also, the transverse bars are typically comprised of a pair of parallel bars slidable relative to each other. The bars are retained in a support housing. Often the bars will wrap or bend in the housing. Thus, there has developed a need to provide an improved transverse bar construction of the type which is easily adjustable in length and which is easily readable. These goals, among others, inspired the present invention.